The U.S. Consumer Financial Protection Bureau is suing Capital One, claiming the company cheated customers out of $2 billion by misleading them.

We strongly disagree with their claims and will vigorously defend ourselves in court.”Capital One stock rose 1.7% on Tuesday.Last fall, the company presented a $35 billion bid to buy Discover Financial Services that is now working its way through the regulatory approval process.

Capital One is being sued by the US government’s consumer watchdog agency for “cheating millions of consumers” and not paying more than $2 billion in interest to holders of its high-interest savings accounts.